main.c revision 60812 
1/* $FreeBSD: head/contrib/less/main.c 60812 2000-05-23 05:51:17Z ps $ */
2/*
3 * Copyright (C) 1984-2000  Mark Nudelman
4 *
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Less License, as specified in the README file.
7 *
8 * For more information about less, or for information on how to
9 * contact the author, see the README file.
10 */
11
12
13/*
14 * Entry point, initialization, miscellaneous routines.
15 */
16
17#include "less.h"
18
19public char *	every_first_cmd = NULL;
20public int	new_file;
21public int	is_tty;
22public IFILE	curr_ifile = NULL_IFILE;
23public IFILE	old_ifile = NULL_IFILE;
24public struct scrpos initial_scrpos;
25public int	any_display = FALSE;
26public POSITION	start_attnpos = NULL_POSITION;
27public POSITION	end_attnpos = NULL_POSITION;
28public int	wscroll;
29public char *	progname;
30public int	quitting;
31public int	secure;
32public int	dohelp;
33public int	more_mode = 0;
34
35#if LOGFILE
36public int	logfile = -1;
37public int	force_logfile = FALSE;
38public char *	namelogfile = NULL;
39#endif
40
41#if EDITOR
42public char *	editor;
43public char *	editproto;
44#endif
45
46#if TAGS
47extern char *	tagoption;
48extern int	jump_sline;
49#endif
50
51extern int	missing_cap;
52extern int	know_dumb;
53
54
55/*
56 * Entry point.
57 */
58int
59main(argc, argv)
60	int argc;
61	char *argv[];
62{
63	IFILE ifile;
64	char *s;
65	extern char *__progname;
66
67#ifdef __EMX__
68	_response(&argc, &argv);
69	_wildcard(&argc, &argv);
70#endif
71
72	progname = *argv++;
73	argc--;
74
75	secure = 0;
76	s = lgetenv("LESSSECURE");
77	if (s != NULL && *s != '\0')
78		secure = 1;
79
80#ifdef WIN32
81	if (getenv("HOME") == NULL)
82	{
83		/*
84		 * If there is no HOME environment variable,
85		 * try the concatenation of HOMEDRIVE + HOMEPATH.
86		 */
87		char *drive = getenv("HOMEDRIVE");
88		char *path  = getenv("HOMEPATH");
89		if (drive != NULL && path != NULL)
90		{
91			char *env = (char *) ecalloc(strlen(drive) +
92					strlen(path) + 6, sizeof(char));
93			strcpy(env, "HOME=");
94			strcat(env, drive);
95			strcat(env, path);
96			putenv(env);
97		}
98	}
99#endif /* WIN32 */
100
101	/*
102	 * Process command line arguments and LESS environment arguments.
103	 * Command line arguments override environment arguments.
104	 */
105	if (strcmp(__progname, "more") == 0)
106		more_mode = 1;
107
108	is_tty = isatty(1);
109	get_term();
110	init_cmds();
111	init_prompt();
112	init_charset();
113	init_line();
114	init_option();
115
116	if (more_mode) {
117		scan_option("-E");
118		scan_option("-m");
119		scan_option("-G");
120		scan_option("-f");
121		s = lgetenv("MORE");
122	} else {
123		s = lgetenv("LESS");
124	}
125	if (s != NULL)
126		scan_option(save(s));
127
128#define	isoptstring(s)	(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
129	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
130	{
131		s = *argv++;
132		argc--;
133		if (strcmp(s, "--") == 0)
134			break;
135		scan_option(s);
136	}
137#undef isoptstring
138
139	if (isoptpending())
140	{
141		/*
142		 * Last command line option was a flag requiring a
143		 * following string, but there was no following string.
144		 */
145		nopendopt();
146		quit(QUIT_OK);
147	}
148
149#if EDITOR
150	editor = lgetenv("VISUAL");
151	if (editor == NULL || *editor == '\0')
152	{
153		editor = lgetenv("EDITOR");
154		if (editor == NULL || *editor == '\0')
155			editor = EDIT_PGM;
156	}
157	editproto = lgetenv("LESSEDIT");
158	if (editproto == NULL || *editproto == '\0')
159		editproto = "%E ?lm+%lm. %f";
160#endif
161
162	/*
163	 * Call get_ifile with all the command line filenames
164	 * to "register" them with the ifile system.
165	 */
166	ifile = NULL_IFILE;
167	if (dohelp)
168		ifile = get_ifile(FAKE_HELPFILE, ifile);
169	while (argc-- > 0)
170	{
171#if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC) || OS2
172		/*
173		 * Because the "shell" doesn't expand filename patterns,
174		 * treat each argument as a filename pattern rather than
175		 * a single filename.
176		 * Expand the pattern and iterate over the expanded list.
177		 */
178		struct textlist tlist;
179		char *gfilename;
180		char *filename;
181
182		gfilename = lglob(*argv++);
183		init_textlist(&tlist, gfilename);
184		filename = NULL;
185		while ((filename = forw_textlist(&tlist, filename)) != NULL)
186			ifile = get_ifile(filename, ifile);
187		free(gfilename);
188#else
189		ifile = get_ifile(*argv++, ifile);
190#endif
191	}
192	/*
193	 * Set up terminal, etc.
194	 */
195	if (!is_tty)
196	{
197		/*
198		 * Output is not a tty.
199		 * Just copy the input file(s) to output.
200		 */
201		SET_BINARY(1);
202		if (nifile() == 0)
203		{
204			if (edit_stdin() == 0)
205				cat_file();
206		} else if (edit_first() == 0)
207		{
208			do {
209				cat_file();
210			} while (edit_next(1) == 0);
211		}
212		quit(QUIT_OK);
213	}
214
215	if (missing_cap && !know_dumb && !more_mode)
216		error("WARNING: terminal is not fully functional", NULL_PARG);
217	init_mark();
218	raw_mode(1);
219	open_getchr();
220	init_signals(1);
221
222
223	/*
224	 * Select the first file to examine.
225	 */
226#if TAGS
227	if (tagoption != NULL)
228	{
229		/*
230		 * A -t option was given.
231		 * Verify that no filenames were also given.
232		 * Edit the file selected by the "tags" search,
233		 * and search for the proper line in the file.
234		 */
235		if (nifile() > 0)
236		{
237			error("No filenames allowed with -t option", NULL_PARG);
238			quit(QUIT_ERROR);
239		}
240		findtag(tagoption);
241		if (edit_tagfile())  /* Edit file which contains the tag */
242			quit(QUIT_ERROR);
243		/*
244		 * Search for the line which contains the tag.
245		 * Set up initial_scrpos so we display that line.
246		 */
247		initial_scrpos.pos = tagsearch();
248		if (initial_scrpos.pos == NULL_POSITION)
249			quit(QUIT_ERROR);
250		initial_scrpos.ln = jump_sline;
251	} else
252#endif
253	if (nifile() == 0)
254	{
255		if (edit_stdin())  /* Edit standard input */
256			quit(QUIT_ERROR);
257	} else
258	{
259		if (edit_first())  /* Edit first valid file in cmd line */
260			quit(QUIT_ERROR);
261	}
262
263	init();
264	commands();
265	quit(QUIT_OK);
266	/*NOTREACHED*/
267}
268
269/*
270 * Copy a string to a "safe" place
271 * (that is, to a buffer allocated by calloc).
272 */
273	public char *
274save(s)
275	char *s;
276{
277	register char *p;
278
279	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
280	strcpy(p, s);
281	return (p);
282}
283
284/*
285 * Allocate memory.
286 * Like calloc(), but never returns an error (NULL).
287 */
288	public VOID_POINTER
289ecalloc(count, size)
290	int count;
291	unsigned int size;
292{
293	register VOID_POINTER p;
294
295	p = (VOID_POINTER) calloc(count, size);
296	if (p != NULL)
297		return (p);
298	error("Cannot allocate memory", NULL_PARG);
299	quit(QUIT_ERROR);
300	/*NOTREACHED*/
301}
302
303/*
304 * Skip leading spaces in a string.
305 */
306	public char *
307skipsp(s)
308	register char *s;
309{
310	while (*s == ' ' || *s == '\t')
311		s++;
312	return (s);
313}
314
315/*
316 * See how many characters of two strings are identical.
317 * If uppercase is true, the first string must begin with an uppercase
318 * character; the remainder of the first string may be either case.
319 */
320	public int
321sprefix(ps, s, uppercase)
322	char *ps;
323	char *s;
324	int uppercase;
325{
326	register int c;
327	register int sc;
328	register int len = 0;
329
330	for ( ;  *s != '\0';  s++, ps++)
331	{
332		c = *ps;
333		if (uppercase)
334		{
335			if (len == 0 && SIMPLE_IS_LOWER(c))
336				return (-1);
337			if (SIMPLE_IS_UPPER(c))
338				c = SIMPLE_TO_LOWER(c);
339		}
340		sc = *s;
341		if (len > 0 && SIMPLE_IS_UPPER(sc))
342			sc = SIMPLE_TO_LOWER(sc);
343		if (c != sc)
344			break;
345		len++;
346	}
347	return (len);
348}
349
350/*
351 * Exit the program.
352 */
353	public void
354quit(status)
355	int status;
356{
357	static int save_status;
358
359	/*
360	 * Put cursor at bottom left corner, clear the line,
361	 * reset the terminal modes, and exit.
362	 */
363	if (status < 0)
364		status = save_status;
365	else
366		save_status = status;
367	quitting = 1;
368	edit((char*)NULL);
369	if (any_display && is_tty)
370		clear_bot();
371	deinit();
372	flush();
373	raw_mode(0);
374#if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
375	/*
376	 * If we don't close 2, we get some garbage from
377	 * 2's buffer when it flushes automatically.
378	 * I cannot track this one down  RB
379	 * The same bug shows up if we use ^C^C to abort.
380	 */
381	close(2);
382#endif
383	close_getchr();
384	exit(status);
385}
386